<HTML>
<BODY BGCOLOR="white">
<PRE>
<FONT color="green">001</FONT>    package org.hackystat.telemetry.analyzer.function.impl;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import org.hackystat.telemetry.analyzer.function.TelemetryFunction;<a name="line.3"></a>
<FONT color="green">004</FONT>    import org.hackystat.telemetry.analyzer.function.TelemetryFunctionException;<a name="line.4"></a>
<FONT color="green">005</FONT>    <a name="line.5"></a>
<FONT color="green">006</FONT>    /**<a name="line.6"></a>
<FONT color="green">007</FONT>     * Accepts either a number or a telemetry stream and returns it. <a name="line.7"></a>
<FONT color="green">008</FONT>     * <a name="line.8"></a>
<FONT color="green">009</FONT>     * @author (Cedric) Qin ZHANG, Philip Johnson<a name="line.9"></a>
<FONT color="green">010</FONT>     */<a name="line.10"></a>
<FONT color="green">011</FONT>    public class IdempotentFunction extends TelemetryFunction {<a name="line.11"></a>
<FONT color="green">012</FONT>    <a name="line.12"></a>
<FONT color="green">013</FONT>      /**<a name="line.13"></a>
<FONT color="green">014</FONT>       * Constructs this instance.<a name="line.14"></a>
<FONT color="green">015</FONT>       */<a name="line.15"></a>
<FONT color="green">016</FONT>      public IdempotentFunction() {<a name="line.16"></a>
<FONT color="green">017</FONT>        super("idempotent");<a name="line.17"></a>
<FONT color="green">018</FONT>      }<a name="line.18"></a>
<FONT color="green">019</FONT>      <a name="line.19"></a>
<FONT color="green">020</FONT>     /**<a name="line.20"></a>
<FONT color="green">021</FONT>      * @param parameters An array of 1 object of type either &lt;code&gt;Number&lt;/code&gt; <a name="line.21"></a>
<FONT color="green">022</FONT>      *        or &lt;code&gt;TelemetryStreamCollection&lt;/code&gt;. <a name="line.22"></a>
<FONT color="green">023</FONT>      * <a name="line.23"></a>
<FONT color="green">024</FONT>      * @return Either an instance of &lt;code&gt;Number&lt;/code&gt; or &lt;code&gt;TelemetryStreamCollection&lt;/code&gt;. <a name="line.24"></a>
<FONT color="green">025</FONT>      * <a name="line.25"></a>
<FONT color="green">026</FONT>      * @throws TelemetryFunctionException If anything is wrong.<a name="line.26"></a>
<FONT color="green">027</FONT>      */<a name="line.27"></a>
<FONT color="green">028</FONT>      @Override<a name="line.28"></a>
<FONT color="green">029</FONT>      public Object compute(Object[] parameters) throws TelemetryFunctionException {<a name="line.29"></a>
<FONT color="green">030</FONT>        if (parameters.length == 1) {<a name="line.30"></a>
<FONT color="green">031</FONT>          return parameters[0];<a name="line.31"></a>
<FONT color="green">032</FONT>        }<a name="line.32"></a>
<FONT color="green">033</FONT>        else {<a name="line.33"></a>
<FONT color="green">034</FONT>          throw new TelemetryFunctionException("Telemetry function " + this.getName()<a name="line.34"></a>
<FONT color="green">035</FONT>              + " takes 1 parameter.");<a name="line.35"></a>
<FONT color="green">036</FONT>        }<a name="line.36"></a>
<FONT color="green">037</FONT>      }<a name="line.37"></a>
<FONT color="green">038</FONT>    }<a name="line.38"></a>




























































</PRE>
</BODY>
</HTML>
